.TH std::relation 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::relation \- std::relation

.SH Synopsis
   Defined in header <concepts>
   template< class R, class T, class U >

   concept relation =                                        \fB(1)\fP \fI(since C++20)\fP
       std::predicate<R, T, T> && std::predicate<R, U, U> &&

       std::predicate<R, T, U> && std::predicate<R, U, T>;

   The concept relation<R, T, U> specifies that R defines a binary relation over the
   set of expressions whose type and value category are those encoded by either T or U.
